The present invention relates to a packaging substrate that exhibits increased heat transfer from an integrated circuit chip or chip package during operation.
The mobile phone market has been driving the development of the advanced semiconductor packaging industry. This is primarily due to the desire of manufacturers to accommodate the end user's demand for functionality, performance and miniaturized form factors.
The mobile phone market's influence was first seen through the demand and subsequent adoption of chip scale packaging (CSP), followed closely by multi-chip packaging and package-on-package (PoP) structures for manufacturing. This trend is most notable in the smart phone segment, where applications, baseband and multimedia processors are increasingly adopting flip chip packaging to satisfy size, performance, and, in some cases, cost requirements.
PoP implemented with flip chip package assembly may effectively solve signal integrity and power integrity. However, thermal problem caused by greater power consumption has become a main challenge in this technical field. As known in the art, during operation of an integrated circuit (IC), an IC chip generates heat, thus heating the entire electronics package that contains the chip. Because the performance of the IC chip degrades as its temperature increases, and because high thermal stresses degrade the structural integrity of the electronics package, this heat must be dissipated.
Some flip chip CSP (FCCSP) packages use a metal lid for this required heat dissipation. The heat from the chip is transferred to the metal lid via a thermally conductive chip/lid interface. The heat is then transferred from the lid to the ambient atmosphere via convection. However, such FCCSP structure requires an extra metal lid and is therefore expensive.